Add 5/21 and 9/40
5/21 + 9/40 is 389/840.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
5/21 = 5 × 40/21 × 40 = 200/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
9/40 = 9 × 21/40 × 21 = 189/840 - Add the two like fractions:
200/840 + 189/840 = 200 + 189/840 = 389/840 - So, 5/21 + 9/40 = 389/840
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